BAGHDAD
— The abduction of four Christian peace activists at gunpoint here is just one part of a spike in the kidnapping and targeting of foreign civilians in Iraq over the past week.

More than a dozen civilians have been victims of this new wave of attacks that is adding twists to an already tense preelection period in Iraq.

In addition to the Western peace activists, the victims include both British and Iranian pilgrims in Iraq to visit Muslim holy sites, a Jordanian businessman, and a German specialist in Mesopotamian archaeology and longtime Iraq resident.

These attacks are reminiscent of an earlier wave of kidnappings and killings last year during which more than 200 foreigners, including journalists and aid workers, were seized. More than three dozen foreigners were killed.

The kidnappings had since tapered off, as many aid workers and other civilians left Iraq or retreated to walled compounds and adopted tighter security measures.

A video showing the four members of the Chicago-based Christian Peacemaker Teams (Tom Fox of Clearbrook, Va.; Norman Kember of London; and James Loney and Harmeet Singh Sooden, both of Canada) claimed to show them in the hands of "Swords of Righteousness," a previously unknown group.

A voice on the video claims they are "spies," but the organization dismissed that accusation, saying in a statement that the four were "committed to telling the truth to US citizens about the horrors of war and its effect on ordinary Iraqi civilians." The organization says its workers are not evangelists but are engaged in "biblically based and spiritually centered peacemaking."

They were kidnapped during a visit to a mosque in Baghdad's western crescent of Sunni neighborhoods on Saturday. They were there to spotlight abuses of suspected Iraqi insurgents in detention, the group made clear in interviews and on its website.

It was a dangerous trip and, perhaps, someone didn't like what the group was doing there.

Speculation over responsibility for the attacks on foreigners has centered on Al Qaeda in Iraq. A German newspaper reported that the German archaeologist, Susanne Osthoff, had received death threats from Al Qaeda in Iraq while working in Mosul last summer. She subsequently moved to Baghdad.

But after an American journalist was kidnapped and killed in Basra earlier this year, speculation about attacks on foreigners began to include shadowy militias associated with sectors of the Shiite-led government. The American journalist Steven Vincent had been writing about the infiltration of Basra's security forces by Shiite militias and paramilitary groups.

The four peace activists could have been targets simply because they are foreigners. In this case, Al Qaeda or a like-minded group would be a suspect. But given that the group was working on human-rights violations against detained Sunnis, other observers say they could have been targeted by Shiite militias.

"It would be what you might call a double advantage for them," says one Iraqi academic who studies the rise of private "mafias" but who asked not to be named. "They stop the activity of these foreigners helping Sunnis, but they also encourage all the suggestions in the press that it is Al Qaeda doing this."

Others say it is simply impossible to know who is responsible.

"We don't know who is doing this because we don't really know what is happening in Iraq," says Wamidh Omar Nadhmi, a political scientist at Baghdad University. "Everything is rumors, but nothing is ever made clear."

The targeting of foreigners is "terrible for Iraq," Dr. Nadhmi says, because in most cases the foreign civilians are here to help Iraqis or "just causes." He notes that Christian Peacemaker Teams has also worked with Palestinians in the West Bank, while the German archaeologist worked to draw attention to the failure of US occupation forces to protect Iraq's archaeological sites.

But he says that the threats foreigners face are a reflection of everyday dangers Iraqis face. "Recently, more than 30 retired military pilots from the war with Iran have been killed, and the rumor is that it is the [work of] Iranian intelligence to get revenge," he says. "Is it so? We don't know."

And he says that after 18 former Baathists [the party of Saddam Hussein] were recently killed in Karbala, the rumor was this it was perpetrated by Shiite security agents. "But again," he says, "no one can say."

Adding to the dismay, he says, is that after the Baathist killings, a special investigative committee was formed to get to the bottom of the killings. "Then the head of the committee was killed three days ago," says Nadhmi. "It is really more puzzling and worrying all the time."